'use strict'
const path = require('path')
const defaultSettings = require('./src/settings.js')

function resolve(dir) {
  return path.join(__dirname, dir)
}

const name = defaultSettings.title || 'vue Admin Template' // page title

// If your port is set to 80,
// use administrator privileges to execute the command line.
// For example, Mac: sudo npm run
// You can change the port by the following methods:
// port = 9528 npm run dev OR npm run dev --port = 9528
const port = process.env.port || process.env.npm_config_port || 9528 // dev port

// // cdn文件
// let cdn = {
//   js: [],
//   css: []

// }
// let externals = {}
// // 通过环境变量 区分是否排除打包 如果是生产环境才需要排除打包
// const isProd = process.env.NODE_ENV === 'production'
// if (isProd) {
//   externals = {
//     // key(包名) / value(这个值 是 需要在CDN中获取js, 相当于 获取的js中 的该包的全局的对象的名字)
//     'vue': 'Vue', // 后面的名字不能随便起 应该是 js中的全局对象名
//     // 'element-ui': 'ELEMENT', // 都是js中全局定义的
//     'xlsx': 'XLSX' // 都是js中全局定义的
//   }
//   cdn = {
//     css: [
//       // 'https://unpkg.com/element-ui/lib/theme-chalk/index.css' // 提前引入elementUI样式
//     ], // 放置css文件目录
//     js: [
//       'https://unpkg.com/vue/dist/vue.js', // vuejs
//       // 'https://unpkg.com/element-ui/lib/index.js', // element
//       'https://cdn.jsdelivr.net/npm/xlsx@0.16.6/dist/xlsx.full.min.js', // xlsx 相关
//       'https://cdn.jsdelivr.net/npm/xlsx@0.16.6/dist/jszip.min.js' // xlsx 相关
//     ] // 放置js文件目录
//   }
// }

// All configuration item explanations can be find in https://cli.vuejs.org/config/
module.exports = {
  /**
* You will need to set publicPath if you plan to deploy your site under a sub path,
* for example GitHub Pages. If you plan to deploy your site to https://foo.github.io/bar/,
* then publicPath should be set to "/bar/".
* In most cases please use '/' !!!
* Detail: https://cli.vuejs.org/config/#publicpath
*/
  publicPath: '/',
  outputDir: 'dist',
  assetsDir: 'static',
  lintOnSave: process.env.NODE_ENV === 'development',
  productionSourceMap: false,
  devServer: {
    port: port,
    open: true,
    overlay: {
      warnings: false,
      errors: true
    },
    // proxy 表示代理配置
    proxy: {
      // 如果请求的 本地服务器的地址包含api 就会触发反向代理
      '/api': {
        // target的值 地址 是我们希望本地服务器【本地后端】代理帮我们访问的最终目标后端服务器
        // 本地前端 => 本地后端 => 其它后端 【ok】
        // 本地前端 => 其它后端 【不ok 跨域】
        target: 'http://ihrm.itheima.net/',
        changeOrigin: true // 表示开启跨域
        // 经过上面的写法 http://localhost:8888/api/login  => http://ihrm-java.itheima.net/api/login
        // pathRewrite: {
        //   '^api': '' 替换为空字符串
        //   如果添加 这个属性 就会替换 http://ihrm-java.itheima.net/login 去掉/api
        // }
      }
    }
    // before: require('./mock/mock-server.js')
  },
  // 配置webpack 文件 vue.config=> 对webpack的升级
  configureWebpack: {
    // provide the app's title in webpack's name field, so that
    // it can be accessed in index.html to inject the correct title.
    name: name,
    resolve: {
      alias: {
        '@': resolve('src')
      }
    }
    // 排除打包这三个文件
    // externals: externals
  },
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    config.plugin('preload').tap(() => [
      {
        rel: 'preload',
        // to ignore runtime.js
        // https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/config/app.js#L171
        fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
        include: 'initial'
      }
    ])
    // 这段代码 在打包时 把cdn变量 注入到 模板文件中 怎么注入到模板 通过args变量
    // config.plugin('html').tap(args => {
    //   // args变量的cdn属性 等于 cdn变量【这个是我们配置的css和js文件】
    //   // args会注入到html模板
    //   args[0].cdn = cdn
    //   return args// 最终返回args值
    // })

    // when there are many pages, it will cause too many meaningless requests
    config.plugins.delete('prefetch')

    // set svg-sprite-loader
    config.module
      .rule('svg')
      .exclude.add(resolve('src/icons'))
      .end()
    config.module
      .rule('icons')
      .test(/\.svg$/)
      .include.add(resolve('src/icons'))
      .end()
      .use('svg-sprite-loader')
      .loader('svg-sprite-loader')
      .options({
        symbolId: 'icon-[name]'
      })
      .end()

    config
      .when(process.env.NODE_ENV !== 'development',
        config => {
          config
            .plugin('ScriptExtHtmlWebpackPlugin')
            .after('html')
            .use('script-ext-html-webpack-plugin', [{
              // `runtime` must same as runtimeChunk name. default is `runtime`
              inline: /runtime\..*\.js$/
            }])
            .end()
          config
            .optimization.splitChunks({
              chunks: 'all',
              cacheGroups: {
                libs: {
                  name: 'chunk-libs',
                  test: /[\\/]node_modules[\\/]/,
                  priority: 10,
                  chunks: 'initial' // only package third parties that are initially dependent
                },
                elementUI: {
                  name: 'chunk-elementUI', // split elementUI into a single package
                  priority: 20, // the weight needs to be larger than libs and app or it will be packaged into libs or app
                  test: /[\\/]node_modules[\\/]_?element-ui(.*)/ // in order to adapt to cnpm
                },
                commons: {
                  name: 'chunk-commons',
                  test: resolve('src/components'), // can customize your rules
                  minChunks: 3, //  minimum common number
                  priority: 5,
                  reuseExistingChunk: true
                }
              }
            })
          // https:// webpack.js.org/configuration/optimization/#optimizationruntimechunk
          config.optimization.runtimeChunk('single')
        }
      )
  }
}
